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CN-121617767-B - Magnetic material for weather-resistant transformer and preparation method thereof

CN121617767BCN 121617767 BCN121617767 BCN 121617767BCN-121617767-B

Abstract

The invention belongs to the technical field of magnetic functional materials, and particularly relates to a magnetic material for a weather-proof transformer and a preparation method thereof. The magnetic material for the weather-proof transformer comprises the following raw materials in percentage by mass: nb 5.2-5.8 wt%, si 11-12.5 wt%, B7.5-8.5 wt%, cu 1.0-1.5 wt%, co 0.1-0.2 wt%, ni 0.05-0.15 wt%, er 0.15-0.35 wt%, modified graphene 2-3 wt%, the balance Fe. The magnetic material prepared by the invention has good soft magnetic performance, excellent high-low temperature stability and outstanding mechanical properties.

Inventors

  • ZHANG PIJIE
  • GUO HONGLI
  • MA RUI

Assignees

  • 山西鑫磁科技有限公司

Dates

Publication Date
20260512
Application Date
20260203

Claims (8)

  1. 1. The weather-proof magnetic material for the transformer is characterized by comprising the following raw materials in percentage by mass, ：Nb 5.2-5.8 wt%、Si 11-12.5 wt%、B 7.5-8.5 wt%、Cu 1.0-1.5 wt%、Co 0.1-0.2 wt%、Ni 0.05-0.15 wt%、Er 0.15-0.35 wt%、 of modified graphene 2-3 wt% and the balance of Fe; the modified graphene is prepared by the following preparation process: (1) Adding graphene into hydrofluoric acid solution for ultrasonic treatment, filtering, washing and drying to obtain acid-treated graphene; (2) Adding the acid-treated graphene and hydrazine hydrate into an electroless plating solution, heating and stirring, filtering, washing and drying to obtain modified graphene; The chemical plating solution comprises, by weight, 10 parts of cobalt chloride, 2-2.5 parts of tantalum chloride, 14-17 parts of sodium citrate, 0.6-1 part of sodium hydroxide and 1200-1600 parts of water.
  2. 2. The magnetic material for the weather-resistant transformer according to claim 1, wherein the mass fraction of the hydrofluoric acid solution in the step (1) is 15-25%, and the dosage ratio of the graphene to the hydrofluoric acid solution is 0.5-1 g:1L.
  3. 3. The magnetic material for the weather-proof type mutual inductor according to claim 1, wherein the mass ratio of the acid treated graphene to the cobalt chloride to the hydrazine hydrate is 1 (10-16) (8-11) based on the amount of the cobalt chloride in the electroless plating solution, and the heating and stirring temperature is 60-90 ℃ and the time is 1-2 h.
  4. 4. A method for producing the magnetic material for a weather-resistant transformer according to any one of claims 1 to 3, comprising the steps of: (a) Heating and stirring all raw materials under the argon atmosphere with the vacuum degree of less than 10 -2 Pa, pouring into a mould, and cooling to obtain a master alloy ingot; (b) Crushing the master alloy ingot, cleaning, melting and then obtaining an amorphous strip through single-roll melt-spinning; (c) And carrying out heat treatment on the amorphous strip, and cooling to obtain the magnetic material.
  5. 5. The method for preparing a magnetic material for a weather-resistant transformer according to claim 4, wherein the specific process of heating and stirring in the step (a) is to keep the temperature at 800-1000 ℃ for 2-5 min, and then raise the temperature to 1500-1600 ℃ and stir for 10-20 min.
  6. 6. The method of claim 4, wherein the roller speed in the single roller spinning process in the step (b) is 40-50 m/s.
  7. 7. The method of claim 4, wherein the heat treatment in step (C) comprises the specific steps of heat treating 7-10 h at 350-575 ℃ and then maintaining 2-4 h at 280-350 ℃ under a transverse magnetic field of 5-20 kA/m.
  8. 8. The method of claim 4, wherein the cooling rate of the cooling in the step (C) is 50 to 80 ℃ per minute.

Description

Magnetic material for weather-resistant transformer and preparation method thereof Technical Field The invention belongs to the technical field of magnetic functional materials, and particularly relates to a magnetic material for a weather-proof transformer and a preparation method thereof. Background In key fields of power systems, rail transit, new energy sources and the like, a mutual inductor is used as core equipment for power metering and relay protection and is often in a severe working environment with alternating high and low temperatures and extreme temperature differences. Currently, the common soft magnetic materials of the conventional transformer on the market mainly comprise silicon steel sheets, permalloy, ferrite, amorphous nanocrystalline alloy and the like. The material generally has the characteristics of high magnetic conductivity, narrow hysteresis loop, small coercive force, easy magnetization and demagnetization and the like, is suitable for alternating current working conditions, and can quickly respond to frequent changes of a magnetic field. The amorphous nanocrystalline alloy has particularly outstanding comprehensive performance, magnetic permeability close to permalloy, iron loss far lower than that of silicon steel sheet (about 1/3 to 1/5 of that of silicon steel sheet), saturation magnetic flux density higher than that of ferrite and permalloy, and good processability and wide application prospect. However, the amorphous nanocrystalline alloy adopted by the conventional transformer is insufficient in weather resistance, and the problems of remarkably reduced magnetic permeability, rapidly increased iron loss and the like easily occur in an extreme temperature environment, so that the measurement accuracy of the transformer is misaligned, the service life is shortened, equipment faults can be even caused, and the stable operation of a power system is influenced. At present, the technical bottleneck of the domestic transformer industry in the research and development of magnetic materials is that the existing component proportion and the heat treatment process are difficult to ensure that the amorphous nanocrystalline material has high magnetic permeability, low iron loss and temperature stability in a wide temperature area, so that the performance stability and reliability of the product in a severe environment are insufficient. In order to improve the technical competitiveness of the transformer product in the application field of high-end severe environments, the precise regulation and control of the grain size, grain boundary structure and internal stress state of the material are realized by optimizing the component proportion of the material, innovating the heat treatment process and other ways, so that the magnetic material for the transformer with wide temperature application range and excellent weather resistance is developed. Disclosure of Invention The first object of the present invention is to provide a magnetic material for a weather-resistant transformer, which has good soft magnetic properties, excellent high-low temperature stability and outstanding mechanical properties. A second object of the present invention is to provide a method for producing the magnetic material for a weather-proof type transformer. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: a magnetic material for a weather-proof type mutual inductor comprises the following raw materials in percentage by mass of ：Nb 5.2-5.8 wt%、Si 11-12.5 wt%、B 7.5-8.5 wt%、Cu 1.0-1.5 wt%、Co 0.1-0.2 wt%、Ni 0.05-0.15 wt%、Er 0.15-0.35 wt%、 modified graphene 2-3 wt% and the balance of Fe. Further, the modified graphene is prepared by the following preparation process: (1) Adding graphene into hydrofluoric acid solution for ultrasonic treatment, filtering, washing and drying to obtain acid-treated graphene; (2) And adding the acid-treated graphene and hydrazine hydrate into the chemical plating solution, heating and stirring, filtering, washing and drying to obtain the modified graphene. Further, in the step (1), the mass fraction of the hydrofluoric acid solution is 15-25%, and the dosage ratio of the graphene to the hydrofluoric acid solution is 0.5-1 g/1L. Further, the electroless plating solution in the step (2) is composed of, by weight, 10 parts of cobalt chloride, 2-2.5 parts of tantalum chloride, 14-17 parts of sodium citrate, 0.6-1 part of sodium hydroxide and 1200-1600 parts of water. Further, based on the amount of cobalt chloride in the electroless plating solution, the mass ratio of the acid treated graphene to the cobalt chloride to the hydrazine hydrate is 1 (10-16) (8-11), the temperature of heating and stirring is 60-90 ℃ and the time is 1-2 h. The preparation method of the magnetic material for the weather-proof transformer comprises the following steps: (a) Heating and stirring all raw materials under argon atmosphere with vacuum degree of <10-2 Pa,